Originally Posted by FKMTB07

You can't randomly space an external cup crankset like Sram/Truvativ or Shimano. The bottom bracket/crank combo is designed for a certain width bb shell and/or number of spacers. In the case of Omniums, it is designed for 68mm shells with no spacers. By adding spacers, you're preventing the non-drive side crank from bottoming out on its stops against the bearing and not seating fully. This is bad.